are u sure about the "e"part? ive never heard of it :PI didn't play usko since a log time and i don't know if it keep working but maybe the "e" combo 'd help. If it does, here i'll explain you it:
1. select your priest enemy
2. press "r"
3. use "e" and just "e" (no "r") before every skill you do, it's one or maybe the best way to cast priest.
Anyway this won't help you much since, as everyone say, all priests are using tbl[/b]